GB1480843A - Electrophotography - Google Patents

Abstract

1480843 Electro-photography CANON KK 18 June 1974 10450/77 Divided out of 1480841 Heading G2H The subject-matter of this Specification is identical with part of that disclosed in parent Specification, but the claims are directed to an electro-photographic process using a perforate screen which comprises a conductive base, a photo-conductive layer on the base and an insulating outer layer on the photo-conductive layer, said insulating outer layer being capable of supporting charge both when the photo-conductive layer is activated and when it is not activated; said process comprising forming a primary electrostatic latent image on said screen and producing, from said primary electrostatic latent image, a plurality of secondary electrostatic latent images, each secondary electrostatic latent image being produced by creating an ion flow of predetermined magnitude towards said screen for modulation by said primary electrostatic latent image and charging a chargeable member with said modulated ion flow, wherein there is applied to the screen for formation of at least the first of said secondary electrostatic latent images, but not for forming at least one subsequent said secondary electrostatic latent image, an additional ion flow of the same polarity as said ion flow of predetermined magnitude such that the quantity of ions in each modulated ion flow is substantially the same.